Fix failing large note imports

When importing to Vaultwarden (or Bitwarden) notes larger then 10_000
encrypted characters are invalid. This because it for one isn't
compatible with Bitwarden. And some clients tend to break on very large
notes.

We already added a check for this limit when adding a single cipher, but
this caused issues during import, and could cause a partial imported
vault. Bitwarden does some validations before actually running it
through the import process and generates a special error message which
helps the user indicate which items are invalid during the import.

This PR adds that validation check and returns the same kind of error.
Fixes #3048

src/api/core/organizations.rs

@@ -1378,6 +1378,12 @@ async fn post_org_import(
     let data: ImportData = data.into_inner().data;
     let org_id = query.organization_id;
 
+    // Validate the import before continuing
+    // Bitwarden does not process the import if there is one item invalid.
+    // Since we check for the size of the encrypted note length, we need to do that here to pre-validate it.
+    // TODO: See if we can optimize the whole cipher adding/importing and prevent duplicate code and checks.
+    Cipher::validate_notes(&data.Ciphers)?;
+
     let mut collections = Vec::new();
     for coll in data.Collections {
         let collection = Collection::new(org_id.clone(), coll.Name);